Huygens 9th Probe Checkout
However, due to high wind in Goldstone, the 70 M DSN antenna that was listening to Cassini for receiving the Huygens real-time data had to be stowed just a few minutes before it received the first Huygens data. So we did not receive any real-time data from the checkout.
For back-up purpose, as part of a checkout sequence, the Probe checkout data are also recorded on board Cassini. It means that the data are not lost, their arrival on Earth is just delayed.
The data have now been 'write protected' on the Cassini Solid State recorder so that they can't be erased by the Orbiter science data that had resumed as planned after the end of the checkout. In the meantime a spacecraft emergency was declared by the Cassini programme manager so that it allowed to stop the Orbiter science and hence avoid Huygens checkout data to be overwritten until it is all safely received at ESOC/HPOC (Huygens Probe Operations Centre).
JPL also managed to downlink a few bits and pieces of the recorded checkout data over the Madrid pass overnight that followed the Goldstone pass. The evaluation of those data by the HPOC team at ESOC indicates that the checkout went as planned. The Madrid pass was also used by JPL to write protect the data and to stop the Orbiter background sequence that runs the Orbiter science. The full playback of the recorded Probe checkout data is expected to occur over a Canberra antenna starting at 02:55 UTC during the night of Tuesday to Wednesday.
Any further information may be directly obtained from:
Dave Salt
Huygens Spacecraft Operations engineer
ESOC/HPOC
Telephone: +49 6151 3085
Report by: Jean-Pierre Lebreton
Huygens Project Scientist